Honduran President Roberto Suazo Cordova and President Reagan are expected to sign a joint communique here today reaffirming U.S. commitments to Honduran security but stopping short of the mutual defense pact Suazo has sought.

Suazo arrived here yesterday for a working visit aimed at bolstering his declining support in Honduras.

"It's a pretty substantial document . . . more than a regular departure statement, but it won't break new ground," a senior White House official said of the communique.

The State Department has also released $75 million in economic aid being withheld until Honduras instituted economic reforms. The package of economic measures promised by Suazo would make the Honduran currency more flexible in relation to other Central American currencies but would not amount to the devaluation Suazo has said he could never accept.

Suazo is struggling in Tegucigalpa to maintain personal control of his party and to pacify peasant groups and labor unions demanding a larger say in the presidential selection process.

His critics are also demanding more security along the country's border with Nicaragua, where Nicaraguan rebels supported by the United States are staging raids into Nicaragua and drawing increased bombardment from the Nicaraguan army.

Suazo is also under considerable pressure from his armed forces to win more U.S. aid and pin down long-range U.S. intentions toward Honduras and the rebels.

Honduran officers have repeatedly expressed concern that, if the U.S. government stops supporting the 15,000 Nicaraguan rebels, that group would be a homeless, jobless and penniless band of armed and dangerous men at large in Honduras.

Honduras sought redefinition of its relationship with the United States last August, after a power shift within the Honduran armed forces elevated leaders skeptical of U.S. objectives. Talks began last August, but sources close to the discussions say little fundamental change has occurred.

In a show of independence, the Honduran government last week promised domestic critics a major effort to dislodge Nicaraguan rebels from their camps. But another senior administration official told reporters yesterday that the Hondurans "have made these statements before" and said he did not know what effect this one would have.

No plans are being drawn to increase aid requests for Honduras, the official said. The administration provided Honduras $214.7 million in economic aid and $62.4 million in military aid last year and has asked for $142.9 million and $88.2 million, respectively, for fiscal 1986.